As an example of the above-described parking assist apparatus, for guiding a vehicle from its stopped position to a target parking position by causing the vehicle to reverse, Patent Document 1 discloses a direct parking guide in which the vehicle is caused to reach the target parking position directly by one time reversing from a stop position and a turnaround parking in which the vehicle is caused to reach the parking target position via at least one reversing and forwarding turnaround. The turnaround parking is effected in case it is not possible to establish any pathway that allows the vehicle to reach the target parking position directly from the stop position even with selecting the maximum steering angle. Therefore, in the turnaround parking, firstly, there is established a guiding pathway to a preliminary target position in the vicinity of the target parking position and the vehicle is reversed along this guiding pathway to reach and stop at the preliminary target position. Thereafter, there is established a further guiding pathway to a forwarding target position to be reached by turning of the steering wheel, so that the vehicles is forwarded along this guiding pathway and stopped at the forwarding target position. Upon arrival at this forwarding target position, there is provided higher possibility for the vehicle to reach the parking target position directly from the forwarding target position, i.e. higher possibility of direct parking operation. Then, if direct parking operation is possible indeed, the vehicle can be guided directly to the parking target position.
Further, Patent Document 2 relating to the above-described parking assist apparatus discloses a technique according to which a vehicle is stopped at a position where a parking lot can be confirmed and then with an operation of a switch, parking assist is initiated. With this parking assist technique, from image data obtained by a camera, a parking lot delimiting line or the like formed on the road surface is obtained, thereby to detect the parking lot delimiting line and then a parking target position is set. Next, a parking pathway calculating section calculates a temporary parking pathway from a temporary reverse travel starting position to determine whether a parking target position can be reached or not. This calculation is effected in repetition with each forwarding of the vehicle. And, if a valid parking pathway has been established, this is reported by a report outputting section through a speaker. In response to this report, the driver will stop the vehicle and then effect an operation for initiating backing of the vehicle, in order to cause the vehicle to travel in reverse along the parking pathway, a guiding section will guide the vehicle to the parking position by means of automatic steering that controls a power steering unit. In this parking assist technique, the turnaround parking mode is not taken into consideration.